Reactivity at the Ln2NiO4þd/electrolyte interface (Ln ¼ La, Nd) studied by Electrochemical Impedance Spectroscopy and Transmission Electron Microscopy

A. MONTENEGRO HERNANDEZ; A. SOLDATI; L. MOGNI; H. TROIANI; A. SCHREIBER; F. SOLDERA; A. CANEIRO

JOURNAL OF POWER SOURCES

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 265 p. 6 - 13

0378-7753

Chemical reactivity between Ln2NiO4þd (Ln: La, Nd) electrodes and Y0.08Zr0.92O1.96 (YSZ) andCe0.9Gd0.1O1.95 (CGO) electrolytes was analyzed by Electrochemical Impedance Spectroscopy (EIS) andFocused Ion Beam-Transmission Electron Microscopy (FIB-TEM) techniques. Ln2NiO4þd electrodes weredeposited onto CGO and YSZ electrolytes by aerography and treated at 900 C during 1 h in order topromote electrode adhesion. EIS spectra were collected between 500 and 800 C in dry air. The PolarizationResistances (PR) values for La2NiO4/CGO/La2NiO4 cell are higher than those of La2NiO4/YSZ/La2NiO4.The PR for both cells and its evolution in time suggest that chemical reactivity is developed at 900 Cduring the adhesion treatment and at T higher than 650 C during the EIS measurements. The PR forNd2NiO4/CGO/Nd2NiO4 and Nd2NiO4/YSZ/Nd2NiO4 are much lower than those of La2NiO4/CGO/La2NiO4and La2NiO4/YSZ/La2NiO4 cells. These values and the slight increase of PR with time for Nd2NiO4 (NNO)electrodes indicate that the strength of chemical reactivity is much lower than that of La2NiO4 (LNO).TEM results confirmed that reactivity between CGO and LNO is much higher than that of YSZ and LNOand also confirm that the strength of reactivity is appreciably lower for NNO as electrode material